package com.tanhua.server.interceptor;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.tanhua.server.utils.Cache;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.MethodParameter;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.http.MediaType;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.http.server.ServletServerHttpRequest;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;

import java.util.concurrent.TimeUnit;

/**
 * @Author YuShiLong
 * @Date 2021/4/15 20:56
 * @Version 1.0
 */
@ControllerAdvice
public class MyResponseBodyAdvice implements ResponseBodyAdvice {

    @Value("${tanhua.cache.enable}")
    private Boolean enable;

    @Autowired
    private RedisTemplate<String, String> redisTemplate;

    private static final ObjectMapper MAPPER = new ObjectMapper();

    @Override
    public boolean supports(MethodParameter methodParameter, Class aClass) {
        //开关处于开启状态，是get请求，包含@Cache注解
        return enable && methodParameter.hasMethodAnnotation(GetMapping.class) && methodParameter.hasMethodAnnotation(Cache.class);
    }

    @Override
    public Object beforeBodyWrite(Object body, MethodParameter methodParameter, MediaType mediaType, Class aClass, ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse) {
        if (null == body) {
            return null;
        }
        try {
            //将数据写入redis中
            //判断o是什么类型的数据
            String redisValue = null;
            if (body instanceof String) {
                redisValue = (String) body;
            } else {
                redisValue = MAPPER.writeValueAsString(body);
            }
            String redisKey = RedisCacheInterceptor.createRedisKey(((ServletServerHttpRequest) serverHttpRequest).getServletRequest());

            Cache cache = methodParameter.getMethodAnnotation(Cache.class);
            //缓存的时间单位是秒
            redisTemplate.opsForValue().set(redisKey, redisValue, Long.valueOf(cache.time()), TimeUnit.SECONDS);
        } catch (Exception e) {
            e.printStackTrace();
        }

        return body;
    }
}
